Manufacture and production of threads, filaments, strips, or films from cellulose esters



Patented July 5, 1927.

UNITED STATES PATENT OFFICE.

LOUIS CLEMENT AND CLEBY RIVIIRE, OF PANTIN, FRANCE, ASSIGNORS.OFONE-HALF TO COURTAULDS LIMITED, OF LONDON, ENGLAND.

MANUFACTURE AND PRODUCTION OF THREADS, FILAMENTS, STRIPS, OR FILMS FROMi CELLULOSE ESTERS.

No Drawing. Application filed November 17, 1924, Serial No. 750,474, andin Great Britain January 5,

This invention consists in an improved process for the precipitation, orcoagulation, of solutions of cellulose esters, for the making ofthreads, filaments, strips, or films. 5 According to this invention asolution of a cellulose ester (such, for example, as cellulose acetate,nitro-cellulose acetate, or n1trocellulose) in a suitable volatileorganic solvent (or mixture of such solvents) is projected throughsuitably shaped orifices, or is otherwise introduced, into asaponifiable animal, or vegetable, oil such, for example, as castor oil,or linseed oil, or a mixture of such oils; On so proceeding thecellulose geneous and. transparent condition. a The ester can then befreed from any excess of oil in any suitable manner. Films, or strips,

produced by this process are very clear and If the product be' strongand are pliable. in the form of fine threads, or filaments, of

artificial silk the said product is very soft other suitable means.

What we claim is 1. The manufacture of cellulosic products whichcomprises introducing a solution conester is rapidly precipitated in ahomo-v taining only cellulose ester and a solvent active setting agent.

miscible with oil, into a setting bath comprising a saponifiable oil asthe active setting agent, and thereafter recovering the solvent from thesetting bath.

In testimony whereof we have signed our names to this specification.

' LOUIS CLEMENT.

CLERY RIVIERE.

